BATC needs to give the user priority

I was descending into EGLL using Beyond ATC. They'd cleared me for the arrival down to FL200. 

Just before getting to FL200 I was handed to London Control. Changed frequency and managed to announce myself on the new frequency to ATC. It then took them five minutes to acknowledge me and then another minute or so to issue me with further descent clearance as they were having to talk to all the other aircraft. By the time they did acknowledge, I was so high on arrival, had to slow right down, speedbrakes and gear out just to get back on track.

Surely a simple solution would be to give the user priority over the artificial users? It doesn't have to be straight away, but a few calls and then acknowledge.

Separately, I've also had issues (probably every other flight) where BATC tells me to 'hold for crossing traffic' during taxi (happens more regularly at EGLL). I'm just left sat there for ten minutes or so, with no sign of crossing traffic. In the end I just keep taxiing and BATC catches up.

It's a great piece of kit, but these seem like really basic features to get right to stop immersion being totally broken. I'm only using the '6' on the traffic slider, so not even that high.